From a European Patent Publication under the Number 0485871 B1 (Barmag) a method is known in which differently colored part-threads, each supplied from a respective cooling shaft, are each guided via a finish application device through a pre-compacting device and subsequently are drawn using a pair of draw rolls, textured in a texturizing nozzle, cooled on a cooling drum, are jointly compacted in an entangling nozzle and subsequently are wound up.
In this arrangement the compacting device between the finish applicator device and the drawing rolls comprises entangling nozzles for each part-thread. These generate the tight entanglement spots known as such. Such tight spots, which prove disadvantageous in the texturizing process are according to this method dissolved again by means of the drawing rolls before the part-threads reach the texturizing nozzle.
The process explained in U.S. Pat. No. 4,025,595 was designed for relatively low spinning speeds in comparison with modern spinning processes. Furthermore, texturized products could be obtained only by subsequent processing of intermediate products obtained in the so-called "spin-draw-winding" process described in the U.S. Patent specification.
The production of similar yarns by modern on-line processing has proved difficult so far, particularly where the continuous processing line includes a texturizing stage. The entangling step disclosed in U.S. Pat. No. 4,025,595 tends to interfere with the performance of the texturizing step.
One approach to this problem can be found in EP-B-485871 and EP-A-434601. In these cases the filament bundles are treated upstream from the texturizing stage to ensure that they remain separate from each other, with the aim of maintaining the "individuality" of each bundle in the final yarn product.
These processes have achieved a degree of success, but they do not provide the yarn producers with the required reliability and flexibility bearing in mind the fact that "yarn producers" constitute a diverse group of organizations with differing marketing and product strategies.